BORING MACHINEBORING MACHINE

CLASSIFICATION OF BORING CLASSIFICATION OF BORING MACHINEMACHINE

The boring machine is one of the The boring machine is one of the vertalile machine tool used to enlarge vertalile machine tool used to enlarge already drilled hole.already drilled hole.

Boring operation can be performed on Boring operation can be performed on lathe as that of turning where tool is lathe as that of turning where tool is stationary and workpiece is rotating.stationary and workpiece is rotating.

But in case of boring is rotating and But in case of boring is rotating and workpiece is stationary which is similar workpiece is stationary which is similar to to

Drilling ,reaming , milling etc.Drilling ,reaming , milling etc. Boring machines can be classified based Boring machines can be classified based

on position of boring tools, accuracy of on position of boring tools, accuracy of work required etc.work required etc.

Boring machines

1. Horizontal Boring Machine (HBM)

2. Vertical Boring

Machine(VBM)

3. Precision (Jig)Boring Machine (PBM)

[1] [1] HORIZONTAL BORING MACHINEHORIZONTAL BORING MACHINE

Horizontal boring Horizontal boring machine contains the machine contains the the majority of boring the majority of boring machines used in mass machines used in mass production.production.

Here boring tool is Here boring tool is rotating while the rotating while the workpiece is stationary.workpiece is stationary.

Work piece is mounted Work piece is mounted on the table which can on the table which can be moved with the help be moved with the help of cross-slide and of cross-slide and saddle.saddle.

Block diagram of horizontal boring Block diagram of horizontal boring machinemachine

Important features of the horizontal Important features of the horizontal boring machines are as following.boring machines are as following.

(1) Head Stock (1) Head Stock

(2) Column(2) Column

(3) Runway (3) Runway

(4) End Support(4) End Support

(5) Table(5) Table

(6)(6) Saddle Saddle

(1) (1) HEAD STOCKHEAD STOCK

It is the most important part of a It is the most important part of a boring machine.boring machine.

It contains spindles.It contains spindles. It supports, drives and feeds the It supports, drives and feeds the

boring tool.boring tool. The spindle rotation is reversible for The spindle rotation is reversible for

backing out tools.backing out tools. Boring tool is held in boring head Boring tool is held in boring head

which will be held in head stock.which will be held in head stock.

(2) (2) COLUMNCOLUMN

Column supports head stock and tail stock.Column supports head stock and tail stock. It guides up and down movement by It guides up and down movement by

means of ways.means of ways. It is hollow and heavily constructed.It is hollow and heavily constructed. To balance head stock and make it easy to To balance head stock and make it easy to

move.move. Columns are keyed, dowelled and bolted Columns are keyed, dowelled and bolted

to the base of the machine.to the base of the machine.

(3) (3) RUNWAYSRUNWAYS

DefinitionDefinition::

When ever the column When ever the column is traversing the base used is known is traversing the base used is known as runway.as runway.

Main function of runways are to carry Main function of runways are to carry the main column, end support the main column, end support column and rotary table if any.column and rotary table if any.

(4) (4) END SUPPORT COLUMNEND SUPPORT COLUMN

DefinitionDefinition:: An out-board bearing is An out-board bearing is

required to support the other end of the required to support the other end of the bar is known as end bar is known as end END SUPPORT END SUPPORT COLUMN.COLUMN.

End support column is necessary in case End support column is necessary in case of long boring and heavy tools are used.of long boring and heavy tools are used.

There is an opened and closed type of end There is an opened and closed type of end support.support.

(5) (5) TABLETABLE

Main function of the table is to Main function of the table is to support for holding the workpiece support for holding the workpiece rigidly during the operation.rigidly during the operation.

Table is equipped with suitable Table is equipped with suitable ranges of feeds as well as quick ranges of feeds as well as quick reverse mechanism.reverse mechanism.

Table moves perpendicular to the Table moves perpendicular to the axis of the spindle.axis of the spindle.

(6) (6) SADDLESADDLE

The main function of saddle is to The main function of saddle is to provide a compound movement of provide a compound movement of the table.the table.

This helps the table to move axially This helps the table to move axially as well as transversly to the spindle.as well as transversly to the spindle.

APLLICATION OF HBMAPLLICATION OF HBM

1.1. Horizontal boring machine can be Horizontal boring machine can be used to drill, bore ream holes.used to drill, bore ream holes.

2.2. These are widely used in batch These are widely used in batch production where workpiece is less.production where workpiece is less.

3.3. These machine can also be used for These machine can also be used for machining type parts like gear machining type parts like gear boxes and engine blocks.boxes and engine blocks.

[2] [2] VERTICAL BORING MACHINE VERTICAL BORING MACHINE (VBM)(VBM)

Schemating Schemating diagram of vertical diagram of vertical boring machine is boring machine is shown in figure.shown in figure.

VBM will be used in VBM will be used in case of length of case of length of the workpiece is the workpiece is less then the less then the diameter.diameter.

Block diagram of vertical boring Block diagram of vertical boring machinemachine

Here the cutting tool is stationary Here the cutting tool is stationary and mounted in the tool head.and mounted in the tool head.

Tool head can be moved linearly or Tool head can be moved linearly or upward and downward motion to upward and downward motion to reach near to the workpiece.reach near to the workpiece.

The workpiece is mounted on the The workpiece is mounted on the table which is rotating.table which is rotating.

Two columns are used to have rigid Two columns are used to have rigid support to the tool head.support to the tool head.

APPLICATION OF VBMAPPLICATION OF VBM

Vertical boring machine is used to Vertical boring machine is used to machine inside and outside diameter.machine inside and outside diameter.

VBM can also be used in for facing VBM can also be used in for facing large size workpiece.large size workpiece.

Different products are turbine casting, Different products are turbine casting, pressure vessels, tables for machine pressure vessels, tables for machine tools, gear blank etc. are machined on tools, gear blank etc. are machined on vertical boring machine.vertical boring machine.

[3] [3] PRECISION(JIG) BORING MACHINEPRECISION(JIG) BORING MACHINE (PBM)(PBM)

Precision or Jig boring machine is used in Precision or Jig boring machine is used in high accuracy toolroom application.high accuracy toolroom application.

Different machine components include Different machine components include jigs, fixtures, gauges etc.jigs, fixtures, gauges etc.

Because of their high precision category Because of their high precision category they can also be used in precision co-they can also be used in precision co-ordinate measuring machines.ordinate measuring machines.

Here the spindle bearing and spindle are Here the spindle bearing and spindle are constructed with very high accuracy.constructed with very high accuracy.

The table is mounted on cross-slide and The table is mounted on cross-slide and saddle for compound movement of the saddle for compound movement of the workpiece.workpiece.

The table can be moved precisely in two The table can be moved precisely in two mutually perpendicular directions in a mutually perpendicular directions in a plan perpendicular to the spindle axis.plan perpendicular to the spindle axis.

Here tolerance upto 0.002mm can me Here tolerance upto 0.002mm can me maintained.maintained.

These machines are costlier. Hence used These machines are costlier. Hence used only in big machine shops, where only in big machine shops, where accuracy is required.accuracy is required.

These machines are also available with These machines are also available with numerical control system.numerical control system.

These machines are provided with These machines are provided with various accessories.various accessories.

Here the first one is the working pbm.Here the first one is the working pbm. The second picture shows the cross The second picture shows the cross

section of the pbm.section of the pbm.